Warned about danger of gangster carrying gun? (7)
I believe the answer is:
Here is my best explanation:
'warned' is the definition.
(alarming is a kind of warning)
'about danger of gangster carrying gun?' is the wordplay.
'about' shows that the letters should be reversed in order.
'danger of gangster' becomes 'dela' (I can't justify this - if you can you should give a lot more credence to this answer).
'carrying' indicates putting letters inside.
'gun?' becomes 'arm' (gun is a kind of arm).
'dela' written backwards gives 'aled'.
'aled' placed around 'arm' is 'ALARMED'.
(Other definitions for alarmed that I've seen before include "Terrified", "Anxious; disturb", "Given a turn", "Worried", "like Icarus as wax melted?", "In a panic", "Frightened, scared", "Frightened, disturbed", "Fear-stricken" and "Startled".)